COASTAL CONSERVANCY Staff Recommendation October 21, 2010 SALT RIVER ECOSYSTEM RESTORATION PROJECT: FINAL DESIGN Project No. 10-024-01 Project Manager: Michael Bowen RECOMMENDED ACTION: Authorization to disburse up to $300,000 to the Humboldt County Resource Conservation District to prepare final designs for the Salt River Ecosystem Restoration Project near Ferndale, Humboldt County. LOCATION: Ferndale, Humboldt County PROGRAM CATEGORY: Resource Enhancement EXHIBITS Exhibit 1: Project Location, Site Map and Graphics Exhibit 2: Salt River Ecosystem Restoration Project DEIR (http://humboldtrcd.org/news__announcements) Exhibit 3: March 8, 2007 Staff Recommendation Exhibit 4: Project Letters RESOLUTION AND FINDINGS: Staff recommends that the State Coastal Conservancy adopt the following resolution pursuant to Sections 31111 and 31251-31270 of the Public Resources Code: “The State Coastal Conservancy hereby authorizes disbursement of an amount not to exceed three-hundred thousand dollars ($300,000) to the Humboldt County Resource Conservation District (“RCD”) for the purpose of developing final designs for the Salt River Ecosystem Restoration Project subject to the condition that prior to the disbursement of funds, the RCD shall submit for the review and approval of the Executive Officer a workplan, including budget and schedule, and the names and qualifications of any subcontractors to be employed on the project, and a signing plan to acknowledge the Conservancy’s funding for these projects.” Staff further recommends that the Conservancy adopt the following findings: “Based on the accompanying staff report and attached exhibits, the State Coastal Conservancy hereby finds that: 1. The proposed project is consistent with the current Project Selection Criteria and Guidelines. Page 1 of 9 SALT RIVER ECOSYSTEM RESTORATION PROJECT: FINAL DESIGN 2. The proposed authorization is consistent with the purposes and objectives of Chapter 6 of Division 21 of the Public Resources Code, regarding enhancement of coastal resources; 3. The project area has been identified in the Humboldt County Local Coastal Program as requiring public actions to resolve existing or potential resource protection problems." PROJECT SUMMARY: Staff recommends the Conservancy authorize the disbursement of up to $300,000 to the Humboldt County Resource Conservation District (“RCD”) to prepare final designs for the Salt River Ecosystem Restoration Project (“Project”) near Ferndale, Humboldt County (See Project Location: Exhibit 1). The RCD is preparing to adopt a Draft Environmental Impact Report (DEIR: Exhibit 2) for the Project. The data and analysis necessary to complete the DEIR was collected and conducted under a prior Conservancy authorization to the County of Humboldt which worked with the RCD and others to help complete the DEIR (Staff Recommendation: Exhibit 3). Providing funds to complete final design will ensure that the RCD will be able to meet its targeted construction date of summer 2011. It also enables the RCD to draw upon construction funds already allocated by a variety of entities for project implementation. If final design is not completed by summer 2012, it is likely that most of the construction funds will be lost. The project is widely supported, and broadly funded (Exhibit 4). The proposed project is comprised of four major components: wetland and upland restoration on the 444-acre Riverside Ranch property; erosion-reduction projects on private lands in the surrounding Wildcat Hills; excavation of a new Salt River channel, also on private lands; and long-term adaptive maintenance, management and continued enhancement of the restored project area. Completing the final engineering design for the restoration component of this project as proposed will ensure that the many benefits outlined in the DEIR, notably significant habitat restoration, and the improvement of agricultural productivity in the Ferndale area, will be achieved as scheduled. The RCD has served as project lead for the Salt River Enhancement Project and is uniquely qualified and appropriate to complete final design in preparation for adoption of the DEIR, completion of the permitting process, and implementation of the proposed project beginning summer 2011. Site Description: The Floodplain of the Eel River extending from the mouth up to the confluence of the Van Duzen River is known as the Eel River Delta. The Delta, located 13 miles south of the City of Eureka, covers approximately 33,000 acres, or 50 square miles (Exhibit 1). Elevations range from sea level at the river mouth to approximately 700 feet in upland areas near Table Bluff and the Wildcat Hills. Most of the delta lands are relatively flat. The Salt River, historically a tidal slough, is the lowermost tributary to the Eel River estuary. The Eel River estuary was once comprised of an intricate network of sloughs, side channels and open water, which, in combination with the tidal exchange and a substantial input of freshwater, provided a hospitable and ever-changing environment for a rich assemblage of aquatic species. The Salt River Watershed can be divided into the upslope tributaries and the alluvial delta. The upslope tributaries drain the Wildcat Hills to the south of Ferndale. The steep slopes in the Wildcat Hills tributaries deliver sediment to the flat alluvial valley floors. Consequently, a series of broad alluvial fans are perched where the tributaries meet the valley floor. Historically, the Page 2 of 9 SALT RIVER ECOSYSTEM RESTORATION PROJECT: FINAL DESIGN streams likely meandered over and around these fans, prior to flowing out to the main Salt River channel. The valley floors of the upland tributaries have, in virtually every case, been converted to pasture, and the tributaries have in many cases been channelized. The Salt River alluvial delta, in contrast with the steep Wildcat tributaries, is characterized by its relatively flat channel slope; elevation of the delta ranges from 3 to 80 feet above mean sea level. Historically, the Salt River was largely influenced by the tide, and was referred to as the “principal slough” of the lower Eel. The historic permanent channel length of the Salt River was 13.4 miles. As such, the Salt River provided extensive and excellent juvenile nursery and rearing conditions for a variety of species, including such commercially important species as salmon, herring, sardine, and Dungeness crabs. This expansive estuarine setting contributed to the Eel River’s prolific salmon and steelhead population, estimated at the turn of the twentieth century to be approximately half a million adult fish. The Eel River Estuary has been significantly altered in the last 150 years. By 1970, the estuary, inclusive of sloughs and side channels, was reduced by tens of thousands of acres to 2,200 acres, or 3.4 square miles. The reduction in estuarine size corresponds with the increase of agricultural land within the delta region, as salt marsh was converted to pasture. It also corresponds to a general decline in the quality and quantity of the estuarine environment, as well as to a marked reduction in the tidal prism of the estuary, probably in direct relation to the decrease in inundated area. This equates to a possible 60 percent reduction in overall tidal prism1. Similarly, the Salt River watershed has been significantly impacted since land use changes accelerated in the late 19th century. The tributaries to the Salt River now contribute large quantities of sediment, associated with timber harvest, grazing practices, road building, and unstable geology. Sediment deposition in combination with individual attempts at channel modification is so severe that the upper portion of the Salt River at the confluence with Williams Creek has been blocked and diverted, resulting in a 42 percent reduction in the size of the Salt River basin; currently the lower Salt River only receives flows from Francis Creek, Reas Creek, and Smith Creek (see Exhibit 1). The upper portion of the Salt River, including Williams Creek, flows northeasterly through Perry Slough/Old River towards the Eel River. The main channel of the Salt River and the lower reaches of its tributaries have become entirely choked with sediment and willows and have lost nearly all hydraulic function upstream of the Reas Creek confluence. The sediment deposits have also significantly reduced channel size in the reach between Reas Creek and the river mouth at the Eel estuary, although tidal influence extends up the Salt River channel adjacent to Riverside Ranch to river mile 3.5 (near the Reas Creek confluence). In addition to excessive sediment load and deposition, historical land reclamation activities such as levee and tide gate construction have resulted in a substantial reduction in tidal influence in the Salt River channel. A small fraction of the original Salt River estuary complex is subject now to tidal exchange. This reduced tidal action has diminished channel scouring and exacerbated sediment deposition. Historically, the Salt River functioned as a large and important component of the Eel River estuary. The Salt River channel, and its many sloughs and tributaries, functioned as important rearing habitat for estuarine species. They also provided a migration corridor for adult salmonids seeking spawning habitat in Salt River tributaries while providing rearing habitat for juveniles migrating downstream to the Eel River estuary. This was especially true for coastal cutthroat 1 The tidal prism is the quantity of water that flows in and out